"In praying to His Father Jesus was acting from His human nature. He is true God AND true man. So His whole life on earth reflected His human nature, from being a helpless baby to suffering and dying on the cross. Praying to the Father is simply another example of this. When He worked miracles, foretold the future and rose from the dead, He was acting from His divine nature."
-----Fr. Vincent Serpa, O.P.
"No. He prayed to the Father. The doctrine of the Trinity states that there are three Persons but one God. The term person answers the question of "Who?" and the term God answers the question "What?" In other words, if you asked the Father, Son, and Holy Spirit who they were, they'd answer "The Father" or "The Son" or "The Holy Spirit" depending on which Person you were addressing. But if you asked all three what they were, all would answer "God." (This is roughly analogous to asking a human being who he is and being told "John Smith," then asking what he is and being told "a human being.") The Person of the Son, who is the God-man Jesus Christ, prayed to the Person of the Father, in union with the Person of the Holy Spirit."